Specs side by side
2 parts compared · 14 differing specs across 14 total parameters.
| Parameter | ||
|---|---|---|
| Supply voltage | - | Same 8V to 35V operating class; the current you command at a given Vref changes with Rsense above. |
| Memory & Peripherals | - | At 0.05 ohm the trip current is Vref x 2.5; at 0.2 ohm it halves - the same trimmer position means different current on different boards, which is why copy-pasted Vref advice fails across brands. |
| Case | QFN-28 (die) / StepStick 16-pin module | StepStick 16-pin module |
| Compatibility Level | - | Functional Equivalent |
| Component Category | Stepper Motor Drivers (StepStick) | - |
| Core & Architecture | - | The unbranded A4988 boards that fill the market: the die is usually the real function, but the sense resistors decide the current math - Pololu originals historically at 0.05 ohm, most clones at 0.1 ohm, some at 0.2 ohm. |
| Firmware Notes | - | Bench procedure before trusting any clone: read the sense resistor marking (or measure), write the formula for that board on a sticker, and set current by the motor rating, never by a remembered voltage from another board. |
| Hardware Notes | - | Same footprint; thermal quality (copper area, heatsink contact) varies widely between clones at the same claimed current. |
| Lead Time Advantage | - | Shenzhen Spot Stock (24-48h Dispatch) |
| Market Reality | The StepStick footprint turned the A4988 into the default stepper driver of desktop 3D printers, CNC routers and camera rigs, and then into a family: the DRV8825 as the 1/32 upgrade in literally the same socket, the TMC2208 as the silent generation designed as an A4988 replacement. The socket is genuinely shared - the Vref arithmetic is not. Each generation sets motor current with a different formula (and different sense resistors on clone boards), so the classic failure of this family is a swap that fits perfectly and drives the motor at twice or half the intended current. This page exists to make the trimmer math explicit before the smoke. | - |
| Reference Part | - | A4988 |
| Role In Circuit | Original Reference Part | - |
| Sourcing Advantage | - | We quote original and clone lanes separately with the Rsense value stated - the formula follows the board. |
| Sourcing Status | Active Shenzhen Spot Sourcing (24–48h) | - |
Parts
- A4988 · allegro-microsystems
- A4988 (clone boards) · allegro-microsystems